The present invention relates to the field of prevention and protection against hazardous situations, particularly in a downhole network integrated into a drill string used in oil and gas exploration, or along the casings and other equipment used in oil and gas production.
Blowouts, high pressure kicks, and loss of circulation are a few of the dangers involved in exploration and production of oil and gas. Many systems have been developed to detect and control these dangers.
U.S. Pat. No. 4,377,206 discloses a device for preventing well blowouts in sucker rod pumping systems and particularly for sensing the parting of a polish rod from a stuffing box and preventing fluid flow through the stuffing box to the atmosphere. The device includes a wear block abutting against a polish rod for sensing when the polish rod parts from the stuffing box. When the polish rod parts from the stuffing box, a lever automatically causes a valve to rapidly close to prevent blowout of the fluid in the well bore.
U.S. Pat. No. 5,006,845 discloses methods for the early detection of gas kicks in marine risers which include monitoring a downhole absolute pressure and a downhole differential pressure of a riser section positioned just above a blowout preventor. Also disclosed is an apparatus comprising a means for telemetering said absolute pressure measurement and said differential pressure measurement from sensors connected to said instrumented riser section to control instrumentation positioned at said sea surface. Said means for telemetering may be an acoustic beacon.
U.S. Pat. Application No. 20040124009, to Hoteit et al., discloses a method and system for averting or mitigating undesirable drilling events during a drilling process. The state of the drilling rig is detected, preferably automatically, based on surface and/or downhole measurement data. One or more undesirable drilling events are detected by correlating the acquired measurement data with the detected state. A drilling rig action is determined which averts or mitigates a detected undesirable drilling event. Finally, the drilling process is overridden by commanding performance of the action.
U.S. application Ser. No. 10/878,243 filed Jun. 28, 2004 in the name of Hall, et al discloses a method and apparatus for use in assessing down-hole drilling conditions. The apparatus includes a drill string, a plurality of sensors, a computing device, and a down-hole network. The sensors are distributed along the length of the drill string and are capable of sensing localized down-hole conditions while drilling. The computing device analyzes data output by the sensors and representative of the sensed localized conditions to assess the down-hole drilling conditions. The method includes sensing localized drilling conditions at a plurality of points distributed along the length of a drill string during drilling operations; transmitting data representative of the sensed localized conditions to a predetermined location; and analyzing the transmitted data to assess the adverse down-hole drilling conditions. An application is also disclosed which may display a notice when some adverse drilling condition is about to occur and corrective or preventative action needs to be taken.